The
classic swipe card uses magnetic strips to encode information and requires a magnetic card reader.
The card in the article you linked to is no such card but an
RFID card. An RFID card requires a card reader that emits a high frequency electromagnetic field. This field is picked up by an antenna on the card and used to power the card's microcontroller. Data is transmitted between the reader and the card by modulating the electromagnetic field. See e.g.
this tutorial.